11-4-2024 VARANASI, INDIA - SWAN GOOSE (Anser cygnoides var. domesticus)

The Chinese is an international breed of domestic goose, known by this name in Europe and in North America. Unlike the majority of goose breeds, it belongs to the knob geese, which derive from Anser cygnoides and are characterised by a prominent basal knob on the upper side of the bill. It originates in China, where there are more than twenty different breeds of knob goose.

Unlike the majority of goose breeds, which derive from the greylag goose (Anser anser), the Chinese belongs to the knob geese, which derive from the swan goose (Anser cygnoides) and are characterised by a prominent basal knob on the upper side of the bill. As the name suggests, it is believed to have originated in China, where there are more than twenty different breeds of knob goose. 

It was seen in Britain from the early eighteenth century if not before,  and was present in the United States in the latter part of that century – George Washington is believed to have kept some on his plantation at Mount Vernon. 

It was included in the first Standard of Perfection of the American Poultry Association in 1874.  

In the twenty-first century it is an endangered breed: it is reported to DAD-IS by seven countries – Australia, Lithuania, Moldova, the Russian Federation, Slovenia, Suriname and the UK – but none of them report population data. Population data was last reported by the United Kingdom in 2002, when there were between 150 and 1000 birds. The Livestock Conservancy in the United States lists it as watch, its third level of concern.

It appears in two varieties: the grey-brown, with colouring similar to that of the wild swan goose (Anser cygnoides), and the white.  The bill and the knob are black in the grey-brown variety, and orange in the white; the shanks and feet are always orange. In birds bred for showing the neck is long and slender. 

As a layer of eggs it is the most prolific of any breed of goose, usually laying some 50–60 eggs in a season of about five months, but sometimes reaching 100 eggs during that time.  The eggs weigh about 120 g, rather less than those of other geese.  Flocks of the geese may be used to guard property or to keep down weeds.

27-7-2019 RIBADESELLA, ASTURIAS - SWAN GOOSE (Anser cygnoides var. domesticus)

6-11-2016 SHANGHAI, CHINA - SWAN GOOSE (Anser cygnoides var. domesticus)

The swan goose was formally described in 1758 by the Swedish naturalist Carl Linnaeus in the tenth edition of his Systema Naturae under the binomial name Anas cygnoides. It is now one of 11 species placed in the genus Anser that was introduced by the French zoologist Mathurin Jacques Brisson in 1760.[6] The specific epithet combines the Latin cygnus meaning "swan" with Ancient Greek -oidēs meaning "resembling". The species is monotypic: no subspecies are recognised.

The swan goose is large and long-necked for its genus, wild birds being 81–94 cm (32–37 in) long (the longest Anser goose) and weighing 2.8–3.5 kg (6.2–7.7 lb) or more (the second-heaviest Anser, after the greylag goose, A. anser). The sexes are similar, although the male is larger, with a proportionally longer bill and neck; in fact the largest females are barely as large as the smallest males. Typical measurements of the wing are 45–46 cm (18–18 in) in males, 37.5–44 cm (14.8–17.3 in) in females; the bill is about 8.7–9.8 cm (3.4–3.9 in) long in males and 7.5–8.5 cm (3.0–3.3 in) in females. The tarsus of males measures around 8.1 cm (3.2 in). The wingspan of adult geese is 160–185 cm (63–73 in).

The upperparts are greyish-brown, with thin light fringes to the larger feathers and a maroon hindneck and cap (reaching just below the eye). The remiges are blackish, as are the entire underwing and the white-tipped rectrices, while the upper- and undertail coverts are white. A thin white stripe surrounds the bill base. Apart from darker streaks on the belly and flanks, the underside is pale buff, being especially light on the lower head and foreneck which are sharply delimited against the maroon. In flight, the wings appear dark, with no conspicuous pattern. Uniquely among its genus, the long, heavy bill is completely black; the legs and feet, on the other hand, are orange as in most of its relatives. The eyes' irides are maroon. Juveniles are duller than adult birds, and lack the white bill base and dark streaks on the underside.

The voice is a loud, drawn-out and ascending honking aang. As a warning call, a similar but more barking honk is given two or three times in short succession.

The swan goose was uplisted from Near Threatened to Vulnerable on the IUCN Red List in 1992 and further to Endangered in 2000, as its population is declining due to habitat loss and excessive hunting and (particularly on the Sanjiang Plain in China) egg collecting. But new research has shown it to be not as rare as it was believed, and consequently, it was downlisted to Vulnerable status again in 2008. Still, less than 500 pairs might remain in Russia, while in Mongolia numbers are unknown, though about 1,000 were seen at Ögii Lake in 1977. Favorite wintering locations in China are Lake Dongting, Lake Poyang, the Yancheng Coastal Wetlands and other locations around the lower Yangtze River, where some 60,000 individuals may be found each year – though this may be almost the entire world population. Until the 1950s, the species wintered in small numbers (up to about 100 birds annually) in Japan, but habitat destruction has driven them away.

31-10-2016 XIAN, CHINA - SWAN GOOSE (Anser cygnoides var. domesticus)

The swan goose (Anser cygnoides) is a large goose with a natural breeding range in inland Mongolia, Northeast China, and the Russian Far East. It is migratory and winters mainly in central and eastern China. Vagrant birds are encountered in Japan and Korea (where it used to winter in numbers when it was more common), and more rarely in Kazakhstan, Laos, coastal Siberia, Taiwan, Thailand and Uzbekistan.

While uncommon in the wild, this species has been domesticated. Introduced and feral populations of its domestic breeds occur in many places outside its natural range. The wild form is also kept in collections, and escapes are not unusual amongst feral flocks of other Anser and Branta geese.

The swan goose was formally described in 1758 by the Swedish naturalist Carl Linnaeus in the tenth edition of his Systema Naturae under the binomial name Anas cygnoides. It is now one of 11 species placed in the genus Anser that was introduced by the French zoologist Mathurin Jacques Brisson in 1760.[6] The specific epithet combines the Latin cygnus meaning "swan" with Ancient Greek -oidēs meaning "resembling". The species is monotypic: no subspecies are recognised.

The swan goose is large and long-necked for its genus, wild birds being 81–94 cm (32–37 in) long (the longest Anser goose) and weighing 2.8–3.5 kg (6.2–7.7 lb) or more (the second-heaviest Anser, after the greylag goose, A. anser). The sexes are similar, although the male is larger, with a proportionally longer bill and neck; in fact the largest females are barely as large as the smallest males. Typical measurements of the wing are 45–46 cm (18–18 in) in males, 37.5–44 cm (14.8–17.3 in) in females; the bill is about 8.7–9.8 cm (3.4–3.9 in) long in males and 7.5–8.5 cm (3.0–3.3 in) in females. The tarsus of males measures around 8.1 cm (3.2 in). The wingspan of adult geese is 160–185 cm (63–73 in).

The upperparts are greyish-brown, with thin light fringes to the larger feathers and a maroon hindneck and cap (reaching just below the eye). The remiges are blackish, as are the entire underwing and the white-tipped rectrices, while the upper- and undertail coverts are white. A thin white stripe surrounds the bill base. Apart from darker streaks on the belly and flanks, the underside is pale buff, being especially light on the lower head and foreneck which are sharply delimited against the maroon. In flight, the wings appear dark, with no conspicuous pattern. Uniquely among its genus, the long, heavy bill is completely black; the legs and feet, on the other hand, are orange as in most of its relatives. The eyes' irides are maroon. Juveniles are duller than adult birds, and lack the white bill base and dark streaks on the underside.

The voice is a loud, drawn-out and ascending honking aang. As a warning call, a similar but more barking honk is given two or three times in short succession.

The swan goose was uplisted from Near Threatened to Vulnerable on the IUCN Red List in 1992 and further to Endangered in 2000, as its population is declining due to habitat loss and excessive hunting and (particularly on the Sanjiang Plain in China) egg collecting. But new research has shown it to be not as rare as it was believed, and consequently, it was downlisted to Vulnerable status again in 2008. Still, less than 500 pairs might remain in Russia, while in Mongolia numbers are unknown, though about 1,000 were seen at Ögii Lake in 1977. Favorite wintering locations in China are Lake Dongting, Lake Poyang, the Yancheng Coastal Wetlands and other locations around the lower Yangtze River, where some 60,000 individuals may be found each year – though this may be almost the entire world population. Until the 1950s, the species wintered in small numbers (up to about 100 birds annually) in Japan, but habitat destruction has driven them away.

Though the majority of domestic geese are descended from the greylag goose (A. anser), two breeds are direct descendants of the swan goose: the Chinese goose and the African goose. These breeds have been domesticated since at least the mid-18th century – perhaps even (in China) since around 1000 BC. They vary considerably from their wild parent in appearance, temperament, and ability to produce meat and eggs; the most conspicuous feature is the prominent bill knob and upright posture.

Charles Darwin studied goose breeds as part of his work on the theory of evolution. He noted that the external differences between Chinese geese and breeds descended from the Greylag goose belied a rather close relationship:

"The hybrids from the common and Chinese geese (A. cygnoides), species which are so different that they are generally ranked in distinct genera, have often bred in this country with either pure parent, and in one single instance they have bred inter se."